<nb-card>
  <nb-card-header>Button Shapes</nb-card-header>
  <nb-card-body>
    <button nbButton shape="rectangle" hero status="primary">Rectangle Hero</button>
    <button nbButton shape="semi-round" outline status="info">Semi-round Outline</button>
    <button nbButton shape="round" size="small" status="success">Round Small</button>
  </nb-card-body>
</nb-card>
